Highly Crowded Twisted Thienylene‐Phenylene Structures: Evidence for Through‐Space Orbital Coupling in a [4]Catenated Topology

Abstract Sterically highly crowded and twisted thienylene‐phenylenes are synthesized and structurally characterized. Single‐crystal X‐ray structure analyses and theoretical studies give evidence of through‐space delocalization of π‐electrons of peripheral (hetero)aromatic rings in toroidal and catenated topology.


Supporting Information 1 H-NMR spectra and high resolution mass spectra (HRMS)
Figure S1 High resolution MALDI FTICR mass spectrum of 9.

Figure S2
1 H-NMR spectrum of 9 measured in tetrachloroethane-d 2 . The colour code is given at the formula (right).

Figure S5
High resolution MALDI FTICR mass spectrum of cyclopentamers 13 (left) and isotopic pattern of the molecular peak (top: experiment, bottom: calculated). The peak at m/z = 1320.1043 corresponds to the molecule plus matrix DCTB.

Figure S6
1 H-NMR spectra of HPLC separated fractions of cyclopentamers 13 measured in CD 2 Cl 2 . Blue circles denote protons in 3-position of thiophenes, green circles in 4-position, and red circles in 5-position.

Figure S8
1 H-NMR spectrum of thienylene-phenylene 14 measured in CD 2 Cl 2 . Blue circles denote protons in 3position of thiophenes, green circles in 4-position, and red circles in 5-position. The black circles correspond to the signals of the benzo[b]thiophene unit.

Figure S9
H,H-COSY spectrum of thienylene-phenylene 14 measured in CD 2 Cl 2 . The black, purple, and yellow circles correspond to the signals of the benzo[b]thiophene unit. Crucial interaction of thiophene protons of benzo[b]thiophene unit is highlighted in red. SCHEME S1 Proposed mechanism for the cobalt-mediated formation of cyclopentamers 11 from butadiyne 7. SCHEME S2 Proposed mechanism for the rhodium-mediated formation of benzo[b]thiophene derivative 12 by from thienylene-phenylene 8.

Figure S10a
Labelled molecular structure from crystal structure analysis of precursor 8. For clarity, only one of the two disordered molecules (cis-trans isomerization at certain thiophene rings) is illustrated. Ellipsoids for non-hydrogen atoms are shown at 50% probability.

Table S1b
Selected bond distances of precursor 8. Table S1c Selected angles of precursor 8. Table S1d Selected torsion angles of precursor 8.

Figure S10b
Packing mode of 8 perpendicular (a) and parallel (b) to the [-5 2 7] plane. Intermolecular interactions have been analysed (see also table S1e): S-S and C-H atomic contacts at distances below van der Waals radii are labelled with cyan and green dotted lines, respectively. Distances between the planes in b) are 4.045 Å.

Table S1e
Intermolecular short contacts, below van der Waals radii, of 8.

Figure S10c
Intramolecular short contacts in hexasubstituted benzene derivative 8 (see also table S1f): Short atomic (C-C and C-S) contacts below van der Waals radii are labelled in cyan. The interactions between ipso-C atoms are highlighted with magenta lines (a). The toroidal short-contact topology is sketched in (b).

Table S1f
Intramolecular short contacts, below van der Waals radii, of 8. Figure S11 Molecular structure of dendrimer 9 with ellipsoids at 50% probability for heavy atoms (a): each penta(hetero)arylphenyl unit has been distinctly coloured. Labelled molecular structure of 9 depicted in two images for clarity: central phenyl ring with two 2-thienyl groups and one penta(hetero)arylphenyl unit (b) and central phenyl ring with the remaining two penta(hetero)arylphenyl units and 2-thienyl group (c). For clarity also, only one of the two disordered molecules (cis-trans isomerization at certain thiophene rings) is illustrated and hydrogen atoms and ellipsoids have been avoided.

Table S2b
Selected bond distances of 9. Table S2c Selected torsion angles of 9. Table S2d Intermolecular short contacts, below van der Waals radii, of 9.

Table S2e
Intramolecular short contacts, below van der Waals radii, between ipso-C atoms of 9. Table S2f Intramolecular short contacts, below van der Waals radii, of 9 excluding contacts between ipso-C atoms.

Figure S12a
Labelled molecular structure from the crystal structure analysis of compound 14 depicted in two images for clarity: central phenyl ring with three 2-thienyl and two 2-thienylethynyl groups (a) and the 7-benzo-[b]thiophene unit (b). For clarity also, only one of the two disordered molecules (cis-trans isomerization at certain thiophene rings) is illustrated. Ellipsoids for non-hydrogen atoms are shown at 50% probability.

Table S3c
Selected bond angles of 14. Table S3d Selected torsion angles of 14.

Figure S12b
Packing mode of 14: perpendicular (a) and parallel (b) to the [9 -4 4] plane. Intermolecular contacts observed between atoms at distances below van der Waals radii are labelled by dotted cyan lines (see also table S3e). The out-of-plane pending 7-benzo[b]thiophene units have been foggy up for clarity. Ellipsoids for non-hydrogen atoms are shown at 50% probability in a) and are omitted in b) for clarity.

Table S3e
Intermolecular short contacts, below van der Waals radii, of 14. Table S3f Intramolecular short contacts, below van der Waals radii, of 14.
Figure S12c Intramolecular short contacts in 14 (see also table S3f): Short atomic (C-C and C-S) contacts below van der Waals radii are labelled in cyan. The interactions between ipso-C atoms are highlighted with magenta lines.